First SuperHot Rock geothermal development to advance

Well at the Newberry project site in Oregon (source: AltaRock Energy)

Seattle-based AltaRock Energy announced the results of a path-breaking comprehensive technical and economic feasibility study, completed in collaboration with Baker Hughes, an energy technology company, and the University of Oklahoma, demonstrating the superior energy density and competitive economics of an engineered geothermal system (EGS) resource in high temperature (>400 °C) impermeable rock at the Newberry Volcano near Bend, Ore. This result is a major step in developing the first SuperHot Rock (SHR) geothermal resource in the United States.

AltaRock defines SuperHot Rock as EGS in high-temperature rock above 400 °C. SuperHot Rock development targets energy densities per well as high as five to 10 times that of both conventional EGS and hydrothermal developments in the 200-250 °C range.

Details of the study will be presented at the World Geothermal Conference, Iceland, October 2021, the Geothermal Rising Conference, San Diego, Calif., October 2021, and the Society of Petroleum Engineers Geothermal Workshop, the Netherlands, December 2021.

For nearly a decade, AltaRock has performed extensive geological, hydrological, and geochemical site characterization at Newberry Volcano to evaluate its potential for EGS development. AltaRock determined that economically viable geothermal development requires greater energy density per well not attainable with conventional EGS temperature targets. As part of this study, historical data was incorporated into coupled hydrogeomechanical models that evaluated the impact of new technologies and methods needed to develop such high temperature resources that are located near the brittle-ductile transition zone. Accessing deeper, hotter rock is the key to SHR economic viability and these conditions can be reached using conventional drilling at <5km depths at Newberry.

• The Reservoir Geomechanics & Seismicity Research Group at the University of Oklahoma utilized AltaRock’s data to conduct numerical simulations ? using a first principles approach ? of fracture propagation and stimulation of deep, hot basement rock found beneath Newberry.
• Baker Hughes’s Reservoir Technical Services experts integrated the Newberry Volcano’s geothermal fracture network into the company’s JewelSuiteTM Subsurface Modeling software. This enabled the modelling of the technical performance and economics of a SuperHot Rock geothermal reservoir and well couplet over a 30-year period.

The analysis concluded that SuperHot Rock resources could achieve a competitive Levelized Cost of Electricity (LCOE) of <$0.05/kilowatt-hour. In comparison, a conventional EGS resource target of 200-230 °C would ? with the same net power output ? produce power at an LCOE >$0.10/kilowatt-hour. The significant cost difference between the two systems results from much higher energy density – SuperHot Rock being five to 10 times higher per well than conventional ESG wells – with one-tenth the water requirements and surface area and infrastructure based on conventional EGS use cases.

“The next generation of geothermal power, SuperHot Rock geothermal, will require development of engineered reservoirs in deep basements where hotter ‘supercritical’ temperatures can yield up to 10 times more energy than a conventional geothermal well,” said Geoff Garrison, vice president of research and development at AltaRock. “Once proven in the field, SuperHot Rock geothermal resources will ultimately provide competitively priced, carbon-free power to far greater markets than can currently be reached by affordable geothermal power. SuperHot Rock geothermal has the smallest environmental footprint of any renewable energy resource, sharply reduces the need for transmission infrastructure, and we believe it has the potential to meet a significant portion of global energy demand by 2050. We are fortunate to collaborate with Baker Hughes and University of Oklahoma to explore this exciting geothermal frontier.”

Ajit Menon, geothermal leader at Baker Hughes, said his company’s participation underscores its commitment to new energy sources.  “As an energy technology company, Baker Hughes has supported the geothermal sector for more than 40 years, providing technology and expertise for some of the world’s most ground-breaking projects,” he said. “The results of our reservoir modelling software show the technical and economic feasibility of SuperHot Rock development. Our collaboration with AltaRock is another example of our strategic focus on new energy frontiers and underlines how our subsurface expertise and digital technologies are accelerating geothermal projects globally.”

Professor Ahmad Ghassemi of the University of Oklahoma added: “With AltaRock and Baker Hughes, we have developed quantitative models based on years of empirical testing data to confirm the technical performance of flowing an engineered geothermal reservoir in the brittle ductile transition zone – where the high heat makes the rock easier to stimulate and create reservoirs for heat extraction.”

These promising results also provide tremendous insight into the advancement of both reservoir development and management as well as power conversion technologies that AltaRock and its technical collaborators are developing. AltaRock Energy anticipates formal demonstration of the first SHR EGS well system by 2025 at Newberry Volcano, followed with commercial development by 2030.

About AltaRock

AltaRock Energy (ARE), technology leaders in Enhanced Geothermal Systems (EGS) development, is raising EGS to massive scale — making clean, affordable, renewable geothermal energy available anywhere and everywhere.

The next generation of geothermal power, we call Superhot Rock Geothermal (SHR), taps into the massive stores of very high-temperature heat deep in the earths’ crust to yield up to 10 times more energy than a conventional geothermal well and allow geothermal to scale globally. We believe SHR is one of the best solutions for replacing and repurposing fossil fueled power plants and meeting the future global demand for clean energy. ARE’s team and partners are focused on the innovating the key technologies needed to massively scale SHR resources around the world. Our journey is starting at our site in Newberry Oregon.  For more information, please visit: http://altarockenergy.com.